This application claims the priority of German patent document 10 2004 029 485.2, filed Jun. 18, 2004, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a shock or impact absorbing structural component, in particular for ships, land vehicles and aircraft or for equipment, machines, installations and building parts.
Shock-absorbing structures are known from the prior art in which additional energy-absorbing layers are arranged in the structure. However, these layers reduce the strength of the structure, and the additional material increases its weight or requires additional space.
German patent document DE 101 29 576 discloses a structural element that has an energy-absorbing layer inserted between two cover layers, at least one of which is load-bearing. The disadvantage of this arrangement is that, whilst these layers take up shocks, it either increases in weight with the same strength, or a reduces strength. In particular, because of the arrangement of the energy-absorbing layer between the cover layers in the case of a load, a notch effect on the cover layers must be reckoned with.
In German patent document DE 101 29 576, on the other hand, dry or low-resin aramide fabric or PBO is used as the energy-absorbing layer and is connected to a load-bearing shell. As a result, tensile forces cannot be transferred transversely to the component plane, so the component is at risk in the case of certain operating loads. Moreover, the two cover layers can also bend apart when pressure forces occur in the plane of the cover shells.
Furthermore, composite structures with the thin cover layers are known from the general prior art that take up the forces in the shell plane and have a core that takes up shear forces. The core is formed from honeycombs or from foamed material which on account of the limited structural space cannot, however, take up great energies, since the absorption route is limited. Superposition of a plurality of sandwich structures is restricted inwardly and outwardly in most cases of application for reasons of space.
One object of the invention, therefore, is to provide a shock-absorbing structural component for various cases of application that presents an optimized solution in terms of weight.
This and other objects and advantages are achieved by the shock absorbent structure according to the invention, in which a shock-absorbing structural component has two cover layers with an intermediate layer arranged between them. The intermediate layer extends in an alternating or convoluted form between the cover layers, and is made of a material that exhibits a greater capacity for elongation prior to breaking than at least one of the cover layers. In particular, the intermediate layer can be formed in an undulating shape, from angular portions, trapezoidally, in the shape of nubs or indentations, or in the shape of an egg carton. It thus has a surface area larger than that of the flat or smoothly curved cover layers.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.